Aromaticity(General Knowledge > General Science ) Questions and answers for exam Preparation

Question 1. Select the incorrect statement

A resonance may sometimes cause sp3 atoms to become sp2 hybridized
Delocalizing one lone pair causes aromaticity
One lone pair will be counted as two pi electrons according to Hickel's equation
Two sigma bonds make up a double bond

Explanation:-

Answer: Option D. -> Two sigma bonds make up a double bond

Question 2. Select the correct statement regarding the aromatic nitrogen molecule

It is sp hybridized
It is not hybridized
It is sp2 hybridized
It is sp3 hybridized

Explanation:-

Answer: Option C. -> It is sp2 hybridized

Question 3. Aromatic rings do not have resonance structures

False
True

Explanation:-

Answer: Option A. -> False

Question 4. Stability sequence: primary carbocation > secondary carbocation > tertiary carbocation

Yes
No

Explanation:-

Answer: Option B. -> No

Question 5. Which of the following is the reactive species in the nitration of benzene?

NO2–
NO2+
NO3
HNO3

Explanation:-

Answer: Option A. -> NO2–

Question 6. The number of delocalised 𝞹 electrons in the benzene ring are

2
4
6
8

Explanation:-

Answer: Option C. -> 6

Question 7. Which of the following statements is not correct regarding aromatic compounds?

aromatic compounds are planar
aromatic compounds have 4n -electrons
aromatic compounds are cyclic
aromatic compounds are generally less reactive than similarly substituted alkenes

Explanation:-

Answer: Option B. -> aromatic compounds have 4n -electrons

Question 8. Which of the following statements is true for benzene?

Two types of C-C bonds are present in benzene
Benzene easily undergoes addition due to unsaturation
𝞹-electrons are delocalised in the benzene ring
Three isomeric forms are formed on monosubstitution of benzene

Explanation:-

Answer: Option C. -> 𝞹-electrons are delocalised in the benzene ring

Question 9. Which of the following is not a characteristic property of arenes?

Resonance
Greater stability
Electroscopic additions
Delocalisation of 𝞹-electrons

Explanation:-

Answer: Option C. -> Electroscopic additions

Question 10. Which of the following is an incorrect description of benzene?

The molecule is planar.
The molecule is aromatic.
The molecule is a 6-membered ring which contains alternating single and double carbon-carbon bonds.
The CCC bond angles are all equal to 120°.

Explanation:-

Answer: Option C. -> The molecule is a 6-membered ring which contains alternating single and double carbon-carbon bonds.